Explosive.



"UNITED STATES PATENT OFFICE.

THQMAS.HAWKINS, F BALMAIN, NEW SOUTH WALES, AUSTRALIA, ASSIGNOR TO POWERITE EXPLOSIVE COMPANY LIMITED,- OF SYDNEY, NEW S UTH WALES, AUS- Patented-Oct. 24, 1916.

TRALIA.

EXPLOSIVE.

1 202,712 Specification of Letters Patent.

No Drawing.

To all whom it may concern.

Be it known that I, THOMAS HAWKINS, a

subject of the King of Great Britain and Ireland, residing at 7 Rowantree street, Balmain, in the State of New South WVales, Commonwealth of Australia, have invented certain new and useful Improvements in Explosives, of which the following is a specification.

This invention relates to an explosive for use in ordnance and small arms, and is devised with the object of providing an explosive compound having in a marked de-. gree the following characteristics :stability under varying conditions of storage, simplicity of manufacture, economy of production, safety in handling, and more particularly great )ower and cleanliness-tl1at is to say the resi ue after firing-is'practically oil.

The explosive is compounded of the following four ingredients :nitroglycerin, nitrocellulose, calcium picrate, and petrolatum; and in this regard bears a strong resemblance to the well known cordite, the difference being in the additional ingredient (calcium picrate) and in the proportions of those ingredients whicharecommon to both.

These features result in a great increase of proved method is thoroughly Washed (to remove all traces of free acid) inan alkaline solution composed'of Water 96 parts, borax explosive force as compared with cordite.

For the purpose of comparison, the percentage composition of my new explosive and of cordite are tabulated hereunder This in.- neutron. Gordite.

In compounding new explosive the nitroglycerin prepared by known and ap- 2 parts, sugar 1 part, and lime 1 to 2 parts;

it is then repeatedly washed in clear fresh 1 Application filed November 11, 1915. Serial N 0. 60,914.

water. By this treatment a nitroglycerin is obtained which clears rapidly and which is stronger than ordinary nitroglycerin, and

safer to handle. The nitrocellulose is boiled in a vacuum apparatus for about 20 minutes at a temperature not exceeding 100 C. in

the said alkaline solution, and then subjected usual manner. This treatment procures an absolutely pure and neutral which is not liable to change.

In 4517.32 grains of nitroglycerin treated in the manner above stated I dissolve as fully as possible 2272.68 grains of nitrocellulose treated as above stated and with-'- the aid of a solvent (acetone) but without Q heat reduce them to a gelatinized condition.

To this gelatinized or colloidal substance I add 140.00 grains of calcium picrate which is soluble therein, and I intimately blendand incorporate them so as to form a homogeneous and uniform substancef Lastly when most of the acetone has evaporated I add 70.00 grains of petrolatum having a flash point of not below 204.5 C. (400 F.

F and continue the mixing for some time until the compound is of a suitable conf sistency to be cut into thin cords or Strips and not completely melting below '30.0 C, (86' by suitable means as in the manufacture of cordite.

preferably a surface of glass, porcelain, or

the like, on which the compound is evenly spread. Wwffif What I clain1 aS my invention is After the adding of the petrolatum the mixing is performed on a table having w An explosive compound comprising ap; 1

proximately 64.53 per cent. of nitro-gl'ycerin, 32.46 per cent.'0f nitro-cellulose, 1 per cent. of petrolatum, and 2 percent. of cal-' cium picrate.

Signed at Sydney, New South Wales,

'Australia, this fifth day of October A.- D.

THOMAS HAWKINS Witnesses WM. NEWTON, EMILY P. BARNETT. 

